Soapbox

An old-timey man with a long moustache is wearing a suit and tophat and standing on top of a soapbox. Behind him, there is a caravan with adverts describing his snake oil.
An actor portrays a snake oil salesman standing on a soapbox at a theme park

A soapbox is a raised platform on which one stands to make an impromptu speech, often about a political subject. The term originates from the days when speakers would elevate themselves by standing on a wooden crate originally used for shipment of soap, or other dry goods, from a manufacturer to a retail store.

The term is also used metaphorically to describe a person engaging in often flamboyant, impromptu, or unofficial public speaking. Hyde Park in London is known for its Sunday soapbox orators, who have assembled at its Speakers' Corner since 1872 to discuss religion, politics, and other topics. In the context of the World Wide Web, blogs can be used as soapboxes and are often used for promotional purposes.